RENEWABLE ENERGY SOURCES

This involves putting up lots of wind turbines in exposed places.

Each wind turbine has it's own generator - the electricity is generated directly from the wind turning the blades, which turn the generator.

ADVANTAGES

• There is no pollution (except in production)
• There is no permanent damage to the landscape

DISADVANTAGES

• They spoil the view
• They can be very noisy
• They aren't very reliable, as when the wind stops so do the turbines
• The initial costs are quite high

Solar cells generate electric currents directly from sunlight. They are often the best source of energy for things like calculators and watches, on a small scale.

ADVANTAGES

• There's no pollution (except in production)
• It is a reliable source of energy - but only in the day
• Energy is free, low running costs

DISADVANTAGES

• High initial costs
• Often not practical/too expensive to connect them to the National Grid

Hydroelectric power usually requires the flooding of a valley by building a dam. 

Rainwater is caught and allowed out through turbines. 

ADVANTAGES

• There's no pollution (except in production)
• It can provide an immediate response to an increased demand for electricity
• Rather reliable (except in times of drought)
• No fuel and minimal running costs

DISADVANTAGES

• Flooding of the valley means rotting vegetation (which releases methane and CO2)
• Loss of habitat
• Look very unsightly when they dry up
• High initial costs

Most large power stations have huge boilers which have to be kept running all night even though demand is very low (surplus of electricity at night). It's surprisingly difficult to find a way of storing this spare energy for later use - pumped storage is one of the best solutions.

Spare night-time electricity is used to pump water up to a higher reservoir. This can then be released quickly during periods of peak demand such as the evening, to supplement the steady delivery from power stations.

USES THE SAME IDEA AS HYDROELECTRICITY BUT ONLY STORES THE POWER - DOES NOT GENERATE

As waves come in to the shore, they provide an up and down motion which can be used to drive a generator.

ADVANTAGES

• There's no polluion (except in production)
• No fuel costs and minimal running costs

DISADVANTAGES

• Spoiling the view
• Hazardous to boats
• Fairly unreliable - no waves when the wind drops
• High initial costs

Using the Sun and Moon's gravity. Tidal barrages are big dams built across river estuaries, with turbines in them. 

As the tide comes in, it fills up the estuary to a height of several metres and drives the turbines. This water can then be let out through the turbines at a controlled pace.

ADVANTAGES

• There's no pollution (except in production)
• Pretty reliable - happens twice a day without fail
• Store energy ready for peak demand
• No fuel costs
• Minimal running costs

DISADVANTAGES

• Prevents boats from getting through
• Spoil the view
• Alters the habitat of wildlife
• High initial costs

This is only possible in volcanic areas where hot rocks lay quite near to the surface. The source of much of the heat is the slow decay of various radioactive elements. 

Steam and hot water rise to the surface and are used to drive a generator.

ADVANTAGES

• Free energy

DISADVANTAGES

• Aren't very many suitable locations
• High costs

Burnt to heat up water. Work like fossil fuels but are renewable energy sources.